Potential Causative Mutation for Melanism in Rats Identified in the Agouti Signaling Protein Gene (Asip) of the Rattus rattus Species Complex on Okinawa Island, Japan Sasamori, Shoichi and Wiewel, Andrew S. and Thomson, Vicki A. and Kobayashi, Motoko and Nakata, Katsushi and Suzuki, Hitoshi, Zoological Science, 34, 513-522 (2017), DOI:http://dx.doi.org/10.2108/zs170027